When two replicas issue the same effect inside a single tick, the engine retains the lower-ordered identity and folds the duplicate into a no-op. The history reads as if the second arrival had always agreed.
Branches drawn from a still-pending event do not vanish; they wait against the meridian until their parent is reconciled, and then merge with the canonical line in a single deterministic step.
The engine treats arrival order as advisory. A canonical timestamp is computed from a hybrid logical clock and re-asserted at every settlement boundary, so wall-clock skew never bleeds into the recorded history.
Determinism is a property of the engine, not a configuration of it. Given an identical seed and an identical scenario, every clock, every grain of paper, every retried fork resolves to the same byte. We do not record what we cannot reproduce.
When a participant defects mid-tick, the engine does not retry quietly. The defection is written into the ledger as an event in its own right, and downstream readers of the timeline can see precisely where the fork diverged from the floor.
The far ridge in this chapter is not a ridge. It is a column of measurements, set so that the baseline of each digit traces the silhouette of a distant range. Hover the ridge to read it as data; otherwise it remains scenery.
The engine speaks one verb — reconcile. Every other operation is a particular flavor of reconciliation: a write is the reconciliation of an empty cell with a value; a retry is the reconciliation of two attempts at the same identity; a snapshot is the reconciliation of a moving floor with a stationary observer.
The API surface is small on purpose. There are four entry points, two of which are inverses, and a single observation channel that streams the canonical history in the order it settled, never in the order it arrived.
# reconcile two events into the canonical floor
use concengine::{Engine, Event, Seed};
let mut engine = Engine::with_seed(Seed::from_hex("0x55d9e598"));
engine.tick(0, [
Event::write("ledger/01", "settled"),
Event::write("ledger/01", "settled"),
]);
for e in engine.history() {
println!("{:08} {} {}", e.index, e.id, e.payload);
}
No photographs. No titles. Just names, set on paper, with a small mark for the kind of work each contributed to the ledger.